Walker has this week signed a new deal, keeping him at the Etihad until 2026, after a summer of speculation over the England international’s future.
The right-back is one of the most decorated players in City’s history, winning 15 major trophies since his arrival in 2017.
Speaking in his pre-match press conference ahead of Saturday’s Premier League trip to West Ham, Guardiola revealed how delighted he and Walker's team-mates are to have the defender tied down.
“Kyle is an important figure for us" he said.
"Not just the Club, the players demanded he could not leave. At the end he decided to stay with his wife and family. It is really important for us.
“I spoke with mates and lots of people and they told me Kyle cannot leave. He has qualities you can’t find across the world.
“He can control the best wingers on the planet, who can do better than him?
“He’s getting better on the ball year by year and after he will compete with Haaland to score goals. He scored against Ukraine so be careful Erling.”
Now 33, the five-time Premier League winner stated in an interview with the Club on Thursday that he still has the desire to chase more trophies.
Guardiola agrees, saying: “His mind is there and here in the pitch. In terms of genetics, few players I've seen like him. They are unique.
“As much as he enjoys and is stable in his life it will not be a problem.”
Walker has captained the side on several occasions early in the season after Ilkay Gundogan’s departure in the summer.
Now the transfer window is closed and Guardiola’s squad is finalised until January, the boss has confirmed the players will vote for their captain in the coming days.
Although the full-back missed out on a starting berth in last season’s Champions League final, Guardiola insists that Walker understood his reasons and that decision didn’t affect their relationship.
“I'm with Kyle six years. We know each other. Kyle when he didn’t play sometimes it’s tactical, never bad behaviour,” he stated.
“We talk and he talk a lot with his mates and the Club and he decided. Playing or not he is really important since day one. Our success belongs to him for the amount of games he has played.
"I was sad not to play him in the Champions League final. The way they are playing the build-up maybe with Manu on the right it would help us a bit.
"Look at his response since in pre-season he was committed in the team and it made me realise how important he is and how he behaves on and off the pitch.”
West Ham v City app coverage
Minute-by-minute text updates will begin in our Matchday Centre two hours before kick-off, whilst our Matchday Live show will begin at 13:50 (UK).
David James, Shaun Wright-Phillips and Keith Curle will be special guests on the latest Matchday Live show, also offering their expert insight at half-time and in greater detail after the final whistle.
They will also answer viewer questions throughout the broadcast, with audience participation actively encouraged on Matchday Live. To get in touch, send a WhatsApp to: +447537186538
During the game you can listen to live audio commentary from Alistair Mann and former City midfielder Michael Brown while our text commentary continues.
Make sure to have push notifications turned on as well, so you can be alerted to key moments in the action, including goals, red cards and the team news.
Highlights and a full-match replay on CITY+ can be viewed following full-time.